LAT is palmitoylated and membrane-associated adaptor protein. It rapidly becomes tyrosine-phosphorylated upon receptor engagement. LAT has nine conserved tyrosine residues of which five have been shown to undergo phosphorylation (Y127, Y132, Y171, Y191 and Y226). Src family kinases, SYK and ZAP-70 efficiently phosphorylate LAT on these tyrosine residues (Jiang & Cheng 2007, Paz et al. 2001). Phosphorylation of LAT creates binding sites for the Src homology 2 (SH2) domain proteins PLC-gamma1, GRB2 and GADS, which indirectly bind SOS, VAV, SLP-76 and ITK (Wange 2000).